Washboard



Patented May 14, 1935 WASHBOABD- Charles To Gilbert, Saginaw, Mich, assignorto National 'Washboard Company, 1 Chicago; 111., a

corporation otuwestfiVirginia v Appuegti necember a, 1934, seria1 1657561649 v V v 7 G 9 .t .l i ms-invention re1 ,tes to-doub1e fecedwash- Fig.2Yisahehldrged'diagraimhatic bottom''dg'e T hoardswharaeterized Hy' rubbing 'surfaces-niade of metl sheets corrugated and secured batek tdwith their-"channels iricrisscross re lotion to other so mesa-m ofone' sheet presents 9/ beam hke subportfor each of" the,

l'ritis or the other- 1mg In my 'eo pendin applieationf eel-151 No.

7245700; meat/my lees-and now Patent 19871232 offJanuary s; 1935,;I-h ave "descrihedand eldimed; a'double-rfaced washboardf of thatfkiridf wherein may made of material thinner mother 'ohjectis to cause eachjconii d' b sheets to behiade" still lighteri'without saerifijoing" faoetomaintaih*its*contect with the other more qlosely by exerting spri g=1ike'--pressure thereon; Another ohjeet js to produce such springicontaet outof 'its norma-l 'mstressedplane; and" holding the edges 1 of the-sheets while undeh such stressi means offthe grooveirrthe weshboard {frame} -'Ili'e presentimprovement 'distiiiguish'es; from fm'y earlier, co peirdih'g application by having the 3 mis irection ofirubbihg-formed with deperaiid ooh uentiy stiffer likecorrugations near Y its: middle-1 and shallowefi e'orrugatiohsi the grooves of the legss Other 'objectsof the inventionappear later in i v legs-- of the washboardi is thet the-seidf stronger-middle corrugations are my heH a-t theirhOttOm and top ends against the walls bribes-grooves theb'ottbm and midale railsf oi thefisi-mei 3onsequently those eorrugatlims Will -tightly engage'and firmly; support 1 the middle areaof the other sheet "when we flatter v fifll beenmforcibly bow i QT Sprung; s that ends-:ofilrits corrugation -im m w h wi e descriptionnf 'a parti e l rl mbodi; m'ntlofthe n ho n the accompanyer mwm which: V

ir-ig' myimprovementsithe rramesndwne of-the rubbingdeees-bedhg-broken awary imparts? 3 View of the left-hand half 'ofthe rubbii g rplfiites" shown-in Fig; 1 as it appears' iwhen seehifibmf belowwith the bottomrailof ithf'eif-ramefremfoveiig Fig; 3 is a diagrammatic fraghienteryside-view? of the partsshown in 2.

new; is a sectional view 1; one 4 -qr: -r'ijg'.; i-.; I

Fig; 5f-is a partsectiohalii-partid agramr'rrgticy s ,view illustrating the slightly bowed: sfiope z im I parted to the corriugatedrubbing iecesfiheh'they -10" areseaLted in thegroove'of theframe; andin clit mg the resultant mutuailyfstre'ssed conditio'r and; the tight bearingeontacts ofthe twoplaltes there byproduced throughout the areafiofthe'zwash -e t 9 Fig. 6 is a sectio al deteihpertly diagrammatie; i

V In the washhoardiframe,ihe'tourfiil l',

,dle rail 2; ottom' a -fs; a 'ndfthe l gs-{ im 5 are of 'usual design, the membersfzi'i; '4; 5 being" 20 formedon their inner faces;w1th;gr9oves 2a.; aa; 7 422,- and 512 that define a. continuousf channel 91 uhifofm"width around the insideofthe. fra ineQ-j In the specific embodiment of myfinventlim whieh'l have chosen for purposes off illustration; sheet 6 i has horizontal eorrugations 'of uniror depth and ofTuniform width 'andQiteh; andf its v honebr geitedl top" marginal edge i w't -f its bottom 'edge are entered'fia'twise ihtothe' grooves 2d and [3a respectively along with the Corrugated ends, as m of -sheet'-1, tin-the mah er indieated diagrammatieallyin FigrG: Thefleffihandjar d right-handmarginm edges of sheet 6 present corrugations that" are received and heldfin. leg groovesla and Sares'peoti eIy; as'seen at lili on member 5, Fig. 1. It will be'understood'tha it the frame members areassembled-"aroundthe"rub:

'thoseelemehtsinto the grooves." :t

1 hing: elements in order, to introduce the edgesoii .1 The-'severeleorrugations ofsheet"'Ifjare'jprefi- 40 erably of .varying depths; [and iriaty al'so,ve ry iih width and pitch. The deepest and widest es lbj 1c;'are in the mid width'ofl'the" ruhbihgarea'; the shallower and narrower"corrugatiohsbeihg rnearer sthelegs.4 and .5. In ;Fig-,& theideehest corrugationsare shownas ofIdepth Y 'ahdi bitch X, ahdthesmaller corrugations a r- "depths Yf and pitch X 'Ihedeepest are preferably about equal' in' depth Y to the :width W of" the grooveimq -,t a The principal area/of sheetziisv-keptvunder v middle-worrugationsbas i'lbga't'lcg 01K co-operatihs' 5'53 sheet I. The sprung sheet 6 is held at its'side edges by the leg grooves 4a and 5a.

The side marginal edges of plate I are also received fiatwise into the leg grooves 4a, 5a. They preferably embrace and tightly hold the ends of the channels or grooves of plate 6 by means of locking tangs 8. That manner of fastening is described in detail and claimed in a co-pending application of Charles W. Sadenwater, Serial No. 737,484, owned by a common assignee and now Patent 1,987,217 of January 8, 1935. The ad-.

vantages of thus fastening together the side mar-' ginal edges of the two sheets 6 and l are, convenience in assembling and preventing therubbing surfaces from creeping relatively to each other when the washboard is in use. and bottom marginal edges of sheets 6 and 7 in grooves 20!. and 30!. need not befa'stened'together.

Sheets 6 and 1, after having beenfastened together; alongtheir leg-engagingedges by tangs 8 but not yet mounted in the grooves of the frame, will lie flat as shown in Fig. 2 when laid on any flat surface. The top edges of all arrises of sheet 6 will then be straight and lie substantially in the same plane- Likewise the points of mutual contact of sheets 6 and I will lie in ahorizontal plane, represented by the line L--L. After theends of the deepest and strongest corrugations of sheet I, as lb and 10, have been en- 7 ter'ed-intheupper and lower grooves 2a and 3a,

theyactlike strong beams capable of withstanding, with only a slight amount of deflection, the pressure brought uponthem by the forcible bowing of sheet 6 which occurs when the side edges of 6 are sprung into the leg grooves 4a and 511 during assembling. This bowing'of sheets Sand fI-is indicated in Fig. 2 by the broken lines at 9. Obviously, the ends of allthe corrugationsof sheet I, both large and small, are received in grooves 211', 3a. The large middle corrugations (Y) nearly or quite fill the grooves, as indicated by the broken lines, Fig. 5, and the ends of the smaller side corrugations (Y') are loose enough in the grooves to permit the bowing of sheet 6 in the direction of the arrow, Fig. 2. The side marginal edges of sheet 6 are received in the grooves 4a and a of legs and 5 when its middle portion is sprung in the manner described.

a The result of springing sheet 6 is to force its middle part tightly against the beam-like corrugations, as lb, 1c, of sheet l-and also to force the top and bottom ends of the smaller corrugations Y of sheet! against the walls of the top varying in depth and size from its middle toward its side edges has the further advantage that it attains improved efficiency and convenience in washing. I For example, in washing heavy coarse material such as bath t'oweling, the relatively wideand deep corrugations in the middle part of the board afford the best washingsurfaoe because the heavier fabric can get down into the bottoms of the rubbing grooves. For washin The top lighter fabrics, as muslins, silks and linens, the shallower and more closely spaced corrugations adjacent'the lateral edges of the surface are especially useful. It lies within the scope of my invention to employ sheet I alone in washboards.

The strength and rigidity of sheet 6 is greatly increased by being sprung to assume a slight outwardly convex curvature, and its weight and cost may therefore be reduced without danger of yielding or becoming deformed in use.

I have found that when sheet 1 is made of 100 to 115 pound stock the transversely corrugated sheet 6 may be made of 80 pound material.

Forclearness in illustrating, the corrugations of both sheets are here shown as having smooth work-engaging surfaces, but they may be provided with appropriate embossments or indentations on their side walls, bottoms, and/or crests in known manner.

While I have shown and described only one embodiment of my invention, I am aware that various modif cations of it may be made. My invention, therefore,is not to be restricted except in so far as may be necessitated by the prior art and the scope of the appended claims.

I have shown and described the edges of; the composite rubbing element as being, received in the grooves formed in the rails and legs and have explained the manner in which the ends of the middle corrugations orarrises, lb, 1c are pressed against the walls of the upper and lower railgrooves 2a and 3:1 by the spring-like action of sheet 6 when the latter is bowed. I have also described 'how, by the same spring-like action, the corrugated ends of sheet 6 are caused to press against the wallsof the leg grooves 4a and 5:1, as at 627. It is obvious thatthe pressure of arrises lb, 10 is against the forward walls of rail grooves and 2b as viewed in Fig. 1, and against the rearward walls of leg grooves 4a and 5a, so that the term grooves as here employed is intended to be understood as designating those walls against which the arrises 1b, 1c and the arrises of plate 6 take their respective bearings underthe described spring action of the composite rubbing element. r Y

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a washboard havingaa frame and interiorly' grooved rails and legs, in combination, a sheet corrugated to present arrises and channels extending throughout its length the direction of rubbing, the ends of said arrises being engaged by the walls of said rail grooves, the arrises near the middle of the sheet being deeper than those near the edges thereof, a secondsheet corrugated'to present arrises and channels extending throughout its width and crosswise of the direction of rubbing, fastening means securing together'in locked relation the marginal side edges of said sheets, said locked side edges being engaged by the walls of the leg grooves, said second corrugated sheet having bearing engagement with the middle arrises -of the first sheet and with walls of the grooves in the legs whereby said second sheet'is kept in a resiliently stressed condition and slightly bowed over the said deeper arrises of the first mentioned sheet.

2. In a washboard having a frame with interiorly grooved rails and legs, in combination, a sheet corrugated to present arrises and channels extending throughout its length in the direction of rubbing, the ends of said arrises being engaged in the grooves of said rails, the arrises. near the middle of the sheet beingdeeperthan those at 2,069,943 I I f the edges thereof, a second sheet corrugated to present arrises and channels extendingthroughout its width crosswise of the direction of rubbing and having the ends of its corrugations received in the leg grooves, and mid-areaof said second corrugated sheet being in'back-to-back engagement with the middle arrises of the first sheet and having the ends of its corrugations in bearing engagement with the walls of the grooves in thelegs whereby the said second sheet is, kept in a resiliently stressed condition and slightly bowed over the said middle arrises of the first mentioned sheet.

3. In a washboard including a frame with rails and legs having bearing walls, in combination, a

sheet corrugated to present arrises and channels extending throughout its length in the direction of rubbing, the ends of certain of said arrises near the middle of the sheet being in bearing engagement with and supported by wallsof said a second sheet corrugated to present arrises and I channels extending throughout its'width cross wise of the direction of rubbing, the mid area of said second corrugated sheet being resiliently bowed in back-to-backengagement with the said middle arrises of the firstsh'eet, the endsof' its corrugations bearing upon walls of the legs in" such manner that the said second sheet is kept in a resiliently stressed condition and slightly bowed 10 upon the said middle arrises of the first mentioned sheet. g

4. A washboard rubbing surface having corrugations extendi'nglengthwise of the direction of rubbing, those corrugations in the mid-area of the rubbing surface being deepest, the others being successively shallower from the mid-area. toward both lateral edges of the surface.

' CHARLES T. GILBERT. 

